What Happens to Digestion When Good Bacteria in the Body Are Out of Balance?

by Joanne Marie

Your digestive tract contains millions of helpful bacteria.

Your body contains billions of bacterial cells, many of them harmless and some even helpful. Often called "normal flora," a large number of these helpful bacteria reside in your digestive tract, primarily in your large intestine, or colon. These healthy bacteria carry out several important functions that help digest your food and keep you free of harmful, pathogenic bacteria. When these bacterial colonies are out of balance, a number of problems may result.

Intestinal Bacteria

Although bacteria reside in many parts of your digestive tract, the great majority are found in your large intestine, where they perform essential functions. According to experts at Southern Illinois University, your colon contains about one billion bacteria per gram of stool, mostly members of the genera Bacteroides, Bifidobacterium and Clostridium. These bacteria help stimulate digestion of food and absorption of nutrients. They also destroy toxic digestive byproducts and synthesize vitamin K. In addition, when your colon contains normal numbers of healthy bacteria, these colonies inhibit the growth of other, pathogenic bacteria you ingest with food.

The Colon

In certain situations, the colonies of good bacteria that inhabit your colon may die. This might occur if you take antibiotics, which can destroy these good microorganisms along with the unhealthy type they are designed to kill, or if you contract an illness such as the flu or a parasitic infection. If this happens, the balance of good versus bad bacteria in your colon is upset and pathogenic organisms can grow out of control. The result is often diarrhea, a condition in which you experience frequent, watery bowel movements. When you have diarrhea, your colon fails to absorb water as it normally would, resulting in loss of fluids. If you develop diarrhea, digestion in general may become impaired and you might lose electrolytes, vitamins and protein that your body would normally absorb.

The Small Intestine

Normally, most healthy intestinal bacteria are present in your colon, with few in the small intestine where many nutrients are absorbed. However, if you have a condition that might cause bacterial imbalance such as Crohn's disease or diabetes, overgrowth of microorganisms can occur in the small intestine, causing potentially serious digestive problems. Bacteria in your small intestine use nutrients to grow, interfering with their absorption by your body and possibly damaging cells in your small intestine. This situation interferes with your normal digestion and can cause diarrhea, abdominal discomfort and, if it persists, malnutrition and weight loss.

Remedies

If the good bacteria in your digestive tract become out of balance and you experience digestive problems, experts at Harvard Medical School recommend consuming probiotic foods. These foods contain live cultures of bacteria similar or identical to the healthy types that live in your colon. Examples include foods such as natto or miso, made by fermenting soybeans, or sauerkraut and kimchi, fermented cabbage dishes. Yogurt that contains live cultures is also a healthy probiotic food. You might also consume probiotic supplements containing live bacteria, available at most health food stores. Consuming prebiotic supplements, which contain indigestible carbohydrates that good bacteria use as food, might also help restore the correct balance of bacteria in your digestive tract.

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About the Author

Joanne Marie began writing professionally in 1981. Her work has appeared in health, medical and scientific publications such as "Endocrinology" and "Journal of Cell Biology." She has also published in hobbyist offerings such as "The Hobstar" and "The Bagpiper." Marie is a certified master gardener and has a Ph.D. in anatomy from Temple University School of Medicine.

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